Previous studies demonstrated that academic year-end changeover is associated with lower quality of care. However, the “July Phenomenon” effect on stroke patients treated with mechanical thrombectomy (MT) has not been previously studied.

A retrospective chart review was performed of all stroke patients who underwent MT at an academic tertiary center between July 2014 and May 2018. Collected variables include demographics, month of admission (July Vs. the other months), baseline National Institutes of Health Stroke Scale (NIHSS), DTG time, rate of successful recanalization (thrombolysis in cerebral infarction (TICI) score≥2B), procedure duration, rate of symptomatic hemorrhagic transformation (sICH) and 90-day modified Rankin scale (mRS). Mann-Whitney test was used to compare median DTG times. Multivariate logistic regression was used to examine the relationship between July thrombectomy and long-term outcome, controlling for patient baseline characteristics.

A total of 471 patients underwent thrombectomy during study period, out of which, 35 (13.7%) patients were admitted in the month of July. There were no differences in the age, sex, admission NIHSS, rate of successful recanalization, procedure duration or rate of sICH between July patients vs. patients who were admitted in other months. Median DTG time was 89 minutes in July (IQR 68.5-105.5) and 83 minutes in the other months (IQR 62.25-105), P=0.513. Good long-term outcome (90-day mRS 0-2) was noted in 15 (42.9%) patients in July and in 184 (42.2%) during the other months (P=0.94). On multivariate analysis, July thrombectomy was not a strong predictor of poor long-term outcome (mRS>2) (OR 1.194, 95% CI 0.01-141.816, P=0.942).

In the studied university hospital, July admissions were not associated with longer DTG time nor worse outcomes, contrary to the general perception of the “July phenomenon.”